1.Leonardo DiCaprio and Kate Winslet

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Ever since starring in Titanic together 20 years ago, the duo have remained extremely close friends. They are even known to go out to dinner with each other and take vacations together, and Kate was also there to support Leo when he finally won an Oscar in 2016.

6.Harry Styles and James Corden

The duo have been smitten with each other for years now. James helped write One Direction's "Best Song Ever" music video in 2013. In 2017, their bromance reached a new level when Harry was the musical guest on The Late Late Show for an entire week.

7.John Stamos and Lori Loughlin

Since playing Jessie and Rebecca on Full House from 1987–1995, John and Lori have stayed very close. You can now catch them posting adorable selfies behind the scenes of Fuller House.

8.Justin Timberlake and Jimmy Fallon

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The duo became best friends after starring in an SNL sketch together in the early 2000s. Now, Justin is a frequent guest on The Tonight Show With Jimmy Fallon.

9.Tina Fey and Amy Poehler

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Tina and Amy met in 1993 at Chicago's ImprovOlympics and have been the queens of comedy ever since. From hosting SNL's Weekend Update together to working on films like Sisters in 2015, Tina and Amy are the best of friends.

10.Penélope Cruz and Salma Hayek

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Penélope and Salma have been BFFs for over 20 years. From Penélope pranking Salma on Punk'd in 2005 to endless selfies together, they are true BFF goals.

13.Oprah Winfrey and Gayle King

When you say BFF, you think of Oprah and Gayle. The duo have been best friends for over 40 years and continue to support each other no matter what.

14.Selena Gomez and Taylor Swift

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The duo met when they were both dating two of the Jonas brothers back in 2008. Recently, Selena posted an adorable video for Taylor's 28th birthday.

15.Adam Sandler and Drew Barrymore

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The duo starred in The Wedding Singer together in 1998. The duo, which starred in The Wedding Singer together in 1998, most recently starred in the comedy Blended in 2014.

16.Jennifer Aniston and Courtney Cox

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The two met on the set of Friends in 1994. Jennifer even guest-starred on Courtney's show Cougar Town in 2010.

17.Naomi Watts and Nicole Kidman

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The duo became BFFs on set of the 1991 film Flirting. Now you can frequently spot them being each other's plus-ones to numerous Hollywood parties and movie premieres.

18.Brad Pitt and George Clooney

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Brad and George have been good friends for over 20 years now and man, have they aged well. Not only have they starred together in films like Ocean's Eleven in 2001, but they even have a long-standing prank war.

20.Mariska Hargitay and Debra Messing

The duo have been extremely close for years, and their adorable Instagram selfies are proof their friendship is still going strong. Whether they're brunching in NYC or exploring LA, they're the perfect BFFs.